Hydraulic wick apparatus and method

ABSTRACT

A roadway wick comprises a perforated drain pipe, and a wicking assembly encasing the perforated drain pipe. The roadway wick is operable to absorb accumulated water under the roadway and conduct and drain the water from under the roadway.

RELATED APPLICATION

This application claims the benefit of U.S. provisional patent application, Application No. 60/556,536 filed on Mar. 26, 2004.

BACKGROUND

Highways and other paved or concrete roadways can be damaged by water or other accumulated liquids under the roadway. The formation of bumps or frost heaves begins as water seeps under the roadway. As the water freezes and expands in cold weather, the resultant ice pushes up the roadway and forms bumps in the road. These road bumps require considerable cost and time to cut out the damaged areas and repave or reapply concrete. Further, such roadway repairs require additional costs in closing down traffic and providing traffic control.

DESCRIPTION OF THE DRAWINGS

Please refer to the following drawing figures accompanying the detailed description of the hydraulic wick apparatus and method.

FIG. 1 is a cross-sectional view of a roadway with a hydraulic wick apparatus installed under the roadway; and

FIG. 2 is a more detailed cross-sectional view of the hydraulic wick apparatus.

DETAILED DESCRIPTION

Please refer to FIG. 1 and FIG. 2, where FIG. 1 is a cross-sectional view of a roadway 26 with a hydraulic wick apparatus 10 installed under the roadway, and FIG. 2 is a more detailed cross-sectional view of the hydraulic wick apparatus 10. The hydraulic wick 10 has a multi-layer construction: an outer pipe 12 functioning as a sleeve outside of a wicking assembly 13 and a perforated drain pipe 20. The outer pipe 12 is used during the installation of the hydraulic wick and may be a 6⅛-inch high-density poly plastic pipe, for example. Other suitable construction and materials may also be used. The wicking assembly 13 may include a layer of rot-proof woven or non-woven fabric layer 14, a layer of filter material 16, and another layer of rot-proof woven or non-woven fabric layer 18. The fabric layers 14 and 18 may be a polyester geotextile or another suitable fabric. The filter materials 16 may include tire crumb rubber, a rock aggregate, sand, a combination of these materials and/or other suitable filter materials. The size of the filter materials may be ⅜-inch chunks, for example. The wicking assembly 13 of the hydraulic wick 10 forms a tube that encase the perforated edge drain pipe 20. The multi-layer wicking assembly 13 may be loosely held together, sewn together, fabricated and/or fastened in a suitable manner. A sturdy anchor rope 21 is also sewn or otherwise fastened to the wicking assembly 13 and extends from one or both ends of the wick apparatus 10. The anchor rope 21 may extend the entire length of the wicking assembly, be fastened to the wicking assembly along its entire length, and extend beyond both ends of the pipe 12. The anchor rope 21 may be made of nylon or another suitable material.

The dimensions provided above are approximate and may vary depending on the application and/or operating environment. Further, the materials provided herein are examples of suitable materials and other materials of suitable properties may also be used. It should be noted that one or more layers of the hydraulic wick 10 may be optional depending on the application or other factors. For example, the wicking assembly may comprise a single layer of filter material that has good wetting and wicking properties (the transport of liquid throughout the fiber surface by means of a capillary force) surrounding the perforated drain pipe 20. The wicking material is preferably durable to endure the harsh operating environment.

A process to install the hydraulic wick 10 is now described. A directional drill or another suitable equipment is used to drill a passageway 24 across and under the roadway 26 and through an area of accumulated water. The passageway 24 has an exit point 22. The exit point 22 is preferably on the other side of the roadway 26 from the passageway entrance point and situated below the entrance point to create a sloping passageway. The passageway entrance and exit point are preferably situated off the roadway and in the shoulders of the roadway. After an appropriate back reamer is attached to the drill rod of the drilling equipment, pre-reaming may be needed, but the use of a polymer such as bentonite may not be needed. A foaming agent, water or another fluid may be used to float excise material out of the passageway 24 during drilling. The hydraulic wick 10 is then pulled into the completed passageway 24 while back reaming. The end of the hydraulic wick 10 is preferably situated at or proximate to the exit point 22. After the hydraulic wick 10 is in place, the anchor rope 21 is secured or anchored at the entrance point of the passageway to a sturdy and fixed object that will not move under stress. The pipe casing 12 is then pulled off of the hydraulic wick 10 and out of the passageway 24, leaving the wicking assembly 13 and the drain pipe 20 in place to drain the accumulated water under the roadway 26. The anchored rope 21 may be untied after the pipe casing 12 is removed.

The wicking assembly 13 and drain pipe 20 of the hydraulic wick 10 remain in place under the roadway to draw any accumulated water and other liquids into the perforated drain pipe 20. The multi-layer materials 14-18 in the wicking assembly 13 act like a wick to absorb, filter and conduct the liquids into the drain pipe 20 that allows the collected liquids to be pulled by gravity and flow out of the exit point 22 of the passageway. The filter materials 14-18 further prevent debris from clogging the perforated drain pipe 20 and ensures the proper operation of the hydraulic wick 10.

The hydraulic wick apparatus and method avoids the costly expense of cutting the highway, traffic control, and repaving or reapplying concrete to repair the roadway. The installation of the hydraulic wick may be performed while traffic is traveling on the roadway, therefore minimizing impact to traffic. Only limited traffic control is needed to ensure driver and road crew safety. 

1. A roadway wick, comprising: a perforated drain pipe; and a wicking assembly encasing the perforated drain pipe.
 2. The roadway wick, as set forth in claim 1, wherein the wicking assembly comprises a layer of filter aggregates sandwiched between first and second layers of wicking fabric.
 3. The roadway wick, as set forth in claim 2, wherein the filter aggregate comprises a material selected from the group consisting of rubber chunks, rock aggregate, and sand.
 4. The roadway wick, as set forth in claim 2, wherein the wicking fabric comprises a woven textile.
 5. The roadway wick, as set forth in claim 2, wherein the wicking fabric comprises a non-woven textile.
 6. The roadway wick, as set forth in claim 1, wherein the wicking assembly forms a tube encasing the perforated drain pipe.
 7. The roadway wick, as set forth in claim 1, further comprising a pipe casing over the wicking assembly and the perforated drain pipe used during installation.
 8. The roadway wick, as set forth in claim 1, further comprising an anchor rope fastened to at least one end of the wicking assembly.
 9. A method comprising: forming a passageway under a roadway, the passageway in fluid communication with accumulated liquids under the roadway; drawing a pipe casing encasing a roadway wick into the passageway, the roadway wick having a perforated drain pipe encased within a wicking assembly; withdrawing the pipe casing; and allowing accumulated liquids to be drawn into the perforated drain pipe through the wicking assembly and drain out of the passageway.
 10. The method of claim 9, wherein drawing a pipe casing encasing a roadway wick into the passageway comprises drawing a pipe casing encasing a wicking assembly and a perforated drain pipe into the passageway.
 11. The method of claim 10, drawing a pipe casing encasing a wicking assembly comprises drawing a pipe casing encasing a layer of filter aggregates sandwiched between first and second layers of wicking fabric.
 12. The method of claim 10, further comprising securing the roadway wick prior to withdrawing the pipe casing.
 13. The method of claim 12, wherein securing the roadway wick comprises fastening an anchor rope fastened to at least one end of the wicking assembly to a fixed object prior to withdrawing the pipe casing.
 14. A method of making a roadway wick, comprising: forming a wicking assembly; and encasing a perforated drain pipe with the wicking assembly.
 15. The method, as set forth in claim 14, wherein forming the wicking assembly comprises sandwiching a layer of filter aggregates between first and second layers of wicking fabric.
 16. The method, as set forth in claim 15, wherein forming the wicking assembly comprises forming a tubular wicking assembly.
 17. The method, as set forth in claim 14, further comprising fastening an anchor rope to at least one end of the wicking assembly.
 18. The method, as set forth in claim 14, further comprising fastening an anchor rope to an entire length of the wicking assembly. 